You draw a circle in space that connects to a creature with which you are familiar. The creature can see and hear you and your surroundings and you can see and hear it and the creatures surroundings. The window can not be passed through and doesn't move for the duration of the spell.  The target of this spell can choose to end the spell early if they so choose.

You can create a window across any distance and even to other planes of existence, but if the target is on a different plane than you, there is a 5 percent chance that the message doesn't arrive.